The VPLS (Virtual Private LAN Services) is one kind of services providing the simulation LAN (Local Area Network) on a MPLS (Multi-protocol Label Switching) network, which can make users access the network from a plurality of points of dispersive geographic locations at the same time and access each other, just like these points directly accessing the LAN. The VPLS combines the advantages of Ethernet and MPLS technologies, which is a simulation of all features of the traditional LAN; and its main purpose is to connect a plurality of LANs formed from the Ethernets and isolated at the region through the MPLS network provided by the operator, so as to make them work as one LAN, thereby forming a virtual private network.
The traffic engineering can be implemented by using an overlapping model on IGP (internal gateway protocols), such as IP over ATM (Asynchronous Transfer Mode), IP over FR (Frame Relay), etc. The overlapping model provides a virtual topological structure above a physical topological structure of the network, thereby extending the space of network design and providing a lot of important functions for supporting traffic and resource control, which can support various traffic engineering policies.
The MPLS TE (MPLS Traffic Engineering) technology has combined the MPLS technology and traffic engineering, and has a lot of advantages: in the process of establishing a LSP (Label Switching Path) tunnel, resources can be preserved and the service quality is guaranteed; the LSP tunnel has various attributes, such as priority, seizing, etc., which can control behaviors of the LSP tunnel conveniently; through a backup path and fast reroute technology, the protection is provided in the case of the link/node disconnection; the load of establishing the LSP tunnel is small, which will not influence the normal services of the network. Just about these advantages, they make the MPLS TE become a very attractive traffic engineering scheme. Through the MPLS TE technology, the service provider is able to fully utilize the existing network resource to provide the diversified services, and meanwhile, can optimize the network resources and perform scientific network management.
The FRR (MPLS TE Fast Reroute) technology is one technology of realizing the local protection of the network. In a network applying the MPLS TE, when the link or node becomes invalid somewhere, the LSP configured with the fast reroute protection can switch the data to a protection link automatically. The MPLS TE FRR, by establishing a local backup path in advance, protects the LSP from being influenced by the link/node fault. When the fault occurs, the device that detects the link/node fault can switch the services from the faulted link to the backup path rapidly, thereby reducing data loss.
Fast response and timely switch are characteristics of the MPLS TE FRR, which can control the interrupted time of services in a very small time period and guarantees the smooth transition of service data; and meanwhile, the header node of the LSP will try to find a new path to reestablish the LSP, and switch the data to the new path. Before the new LSP is established successfully, the service data will be forwarded through the protection path all the time.
The typical networking of VPLS includes devices of a custom edge network device (Custom Edge, CE), a provider edge network device (Provider Edge, PE), a backbone network core router (Provider Router, P), etc. An interface device in the VPLS network supports broadcasting, forwarding and filtering Ethernet packets. The PEs interconnect with each other through Pseudo Wires (PW), which forms a simulation LAN to the customer. Each PE needs to not only learn the MAC (Media Access Control) address of the Ethernet message from the PW, but also learn the MAC address from the CE connected with itself. The PW usually uses the MPLS tunnel to finish the data transparent transmission between the PEs, and the tunnel can be an LDP (Label Distribution Protocol), an RSVP-TE (Resource ReSerVation Protocol-Traffic Engineering), etc. The PE is usually an MPLS edge router, and can establish tunnels to other PEs.
However, the reliability of the link between the PEs still needs to be improved. In particular, reducing the loss of the VPLS network flow after the link or node is invalid, it needs to protect the link between the PEs, i.e., the tunnel to construct the PW.
Content of the Invention
The technical problem that the present invention requires to solve is to provide a method and device for a link protection in a virtual private local area network, which solves the problem of rapidly switching and recovering of the flow when the VPLS flow is interrupted.
In order to solve the above-mentioned problem, the present invention provides a method for a link protection in a virtual private local area network, comprising:
in a networking process of a virtual private local area network services (VPLS) network, a link protection device establishing a main tunnel and a standby tunnel of multi-protocol label switching (MPLS) traffic engineering (TE) for a link, and creating a VPLS forwarding table to organize information of the established MPLS TE main tunnel and standby tunnel; and
when receiving a VPLS message, the link protection device searching the information of the MPLS TE main tunnel of transmitting the VPLS message according to a way of accessing the VPLS network of the VPLS message and the VPLS forwarding table, and if the found MPLS TE main tunnel is invalid, then transmitting the received VPLS message by adopting the standby tunnel of the MPLS TE main tunnel.
In the above-mentioned method, the VPLS forwarding table comprises a VPLS broadcast forwarding table, a VPLS media access control (MAC) forwarding table, a TE fast reroute (FRR) table and a next hop output port table.
The above-mentioned method further comprises: the link protection device creating a VPLS access attribute table according to a networking structure of the VPLS network; wherein, the step of the link protection device creating the VPLS forwarding table to organize the information of the established MPLS TE main tunnel and standby tunnel comprises: the link protection device creating the VPLS forwarding table according to the networking structure of the VPLS network; organizing various VPLS accessing ways and a corresponding relation of the VPLS broadcast forwarding table and the VPLS MAC forwarding table in the VPLS forwarding table through the VPLS access attribute table, organizing the information of the established MPLS TE main tunnel and information whether the established MPLS TE main tunnel has a standby tunnel through the VPLS broadcast forwarding table and the VPLS MAC forwarding table, organizing a corresponding relation of the MPLS TE main tunnel and standby tunnel and the next hop output port table in the VPLS forwarding table through the TE FRR table in the VPLS forwarding table, and organizing an output port of the MPLS TE main tunnel and standby tunnel through the next hop output port table.
In the above-mentioned method, both the VPLS broadcast forwarding table and the VPLS MAC forwarding table of the VPLS forwarding table comprise a TE FRR flag bit; and
the step of the link protection device organizing the information whether the established MPLS TE main tunnel has a standby tunnel through the VPLS broadcast forwarding table and the VPLS MAC forwarding table comprises: the link protection device organizing whether the established MPLS TE main tunnel has a standby tunnel through the TE FRR flag bit; when the TE FRR flag bit is valid, indicating that the established MPLS TE main tunnel has a standby tunnel, and when the TE FRR flag bit is invalid, indicating that the established MPLS TE main tunnel does not have a standby tunnel.
In the above-mentioned method, the step of the link protection device searching the information of the MPLS TE main tunnel of transmitting the VPLS message according to a way of accessing the VPLS network of the VPLS message and the VPLS forwarding table comprises: the link protection device searching the information of the MPLS TE main tunnel of transmitting the VPLS network message organized in the VPLS broadcast forwarding table or the VPLS MAC forwarding table by the VPLS access attribute table according to the way of accessing the VPLS network of the VPLS network message;
if the found MPLS TE main tunnel is invalid, then the step of transmitting the received VPLS message by adopting the standby tunnel of the MPLS TE main tunnel comprises: the link protection device judging that the MPLS TE main tunnel has a standby tunnel through the VPLS broadcast forwarding table or the VPLS MAC forwarding table, searching the output port of the standby tunnel of the MPLS TE main tunnel in the next hop output port table through the organization of the TE FRR table, and transmitting the VPLS network message by adopting the standby tunnel.
The present invention further provides a device for a link protection in a virtual private local area network, comprising a platform protocol processing module, a table entry writing processing module and a data forwarding processing module, wherein:
the platform protocol processing module is configured to, in a networking process of a virtual private local area network services (VPLS) network, establish a main tunnel and a standby tunnel of multi-protocol label switching (MPLS) traffic engineering (TE) for a link;
the table entry writing processing module is configured to create a VPLS forwarding table to organize information of the MPLS TE main tunnel and standby tunnel established by the platform protocol processing module; and
the data forwarding processing module is configured to, when receiving a VPLS network message, search the information of the MPLS TE main tunnel of transmitting the VPLS network message according to a way of accessing the VPLS network of the VPLS network message and the created VPLS forwarding table, and if the found MPLS TE main tunnel is invalid, then transmit the received VPLS network message by adopting the standby tunnel of the MPLS TE main tunnel.
In the above-mentioned device, the VPLS forwarding table created by the table entry writing processing module comprises a VPLS broadcast forwarding table, a VPLS media access control (MAC) forwarding table, a TE fast reroute (FRR) table and a next hop output port table.
In the above-mentioned device, the table entry writing processing module is further configured to create a VPLS access attribute table;
wherein, the VPLS access attribute table is configured to organize various VPLS accessing ways and a corresponding relation of the VPLS broadcast forwarding table and the VPLS MAC forwarding table in the VPLS forwarding table;
both the VPLS broadcast forwarding table and the VPLS MAC forwarding table are configured to organize the information of the established MPLS TE main tunnel and information whether the MPLS TE main tunnel has a standby tunnel;
the TE FRR table in the VPLS forwarding table is configured to organize a corresponding relation of the MPLS TE main tunnel and standby tunnel and the next hop output port table in the VPLS forwarding table; and
the next hop output port table is configured to organize an output port of the MPLS TE main tunnel and standby tunnel.
In the above-mentioned device, both the VPLS broadcast forwarding table and the VPLS MAC forwarding table comprise a TE FRR flag bit; and the link protection device organizes whether the established MPLS TE main tunnel has a standby tunnel by the TE FRR flag bit, when the TE FRR flag bit is valid, indicates that the established MPLS TE main tunnel has a standby tunnel, and when the TE FRR flag bit is invalid, indicates that the established MPLS TE main tunnel does not have a standby tunnel.
In the above-mentioned device, the data forwarding processing module is further configured to search the information of the MPLS TE main tunnel of transmitting the VPLS network message organized in the VPLS broadcast forwarding table or the VPLS MAC forwarding table by the VPLS access attribute table according to the way of accessing the VPLS network of the VPLS network message; and
if the found MPLS TE main tunnel is invalid, and when judging that the MPLS TE main tunnel has a standby tunnel through the VPLS broadcast forwarding table, search the output port of the standby tunnel of the MPLS TE main tunnel in the next hop output port table through the organization of the TE FRR table, and transmit the VPLS network message by adopting the standby tunnel.
The technical scheme of the present invention can improve the local protection function of the network and reduce the loss of the service volume.